1. Field of the Invention
The present invention relates to a neck rod member for stringed instruments, particularly for bass guitars. The rod member includes two oblong rod portions which extend parallel relative to each other and essentially contact one another. At one end of the rod member, the rod portions are fixedly connected to each other, for example, by riveting. At the other free ends of the rod portions, a means for effectively shortening the length of one of the rod portions relative to the effective length of the other rod portion is provided. The neck of the instrument defines an oblong blind-end hole which is open at the free end of the neck. The rod member can be inserted into the blind-end hole in such a way that the means for shortening the effective length of the first rod portion is accessible from the open end of the blind-end hole.
2. Description of the Prior Art
A neck rod member of the above-described type is known from U.S. Pat. No. 4,308,780 and German Utility Model No. 78 24 673. Such a neck rod member is inserted into the oblong blind-end hole in the neck of the instrument. The rod member is secured in this hole once one of the rod portions is braced within the hole, as described in detail below. Consequently, a separate means for fastening the rod member in the hole of the neck of the instrument is not necessary. The effective length of one of the rod portions is shortened relative to the other rod portion by rotating a cap nut. As a result, the rod member which previously was straight becomes curved into an arc and, thus, the neck of the instrument also assumes the shape of an arc, wherein the convex side of the arc faces the strings resting on the fingerboard of the neck. The above-described bracing action counteracts the relatively strong tension exerted on the neck of the instrument by the strings. Without the bracing action, the danger exists that the tension of the strings will bend or even break the neck of the instrument.
However, in some stringed instruments, particularly in special types of bass guitars, it may be required, for example, due to the grain of the wood of the neck or for other reasons, that the neck rod member should exert a force on the neck of the instrument which is directed in the same direction as the tension force of the strings. The neck rod member of the type described above is not suitable for this purpose.
U.S. Pat. No. 4,557,174 describes a neck rod member which consists of a single piece. This rod member is inserted into the neck of the instrument and is approximately in the middle thereof fixedly connected to the neck of the instrument by an anchoring means. The rod member must be bent into the desired direction before being inserted. Because of this and particularly due to the fixed anchoring of the rod member in the neck of the instrument, an instrument equipped with the neck rod member according to U.S. Pat. No. 4,557,174 is complicated and expensive to manufacture. In addition, this neck rod member cannot be replaced once it becomes useless or damaged. Accordingly, the neck rod member according to U.S. Pat. No. 4,557,174 is of a considerably different type from the one described initially hereinabove.
It is, therefore, the primary object of the present invention to provide a rod member of the type initially described which can be deformed optionally into a convex or concave arc shape relative to the neck of the instrument. However, the advantages of loosely inserting the rod member into the blind-end hole of the instrument neck and the loose removal therefrom are to be maintained.